Siemens RuleStream documentation explains the RuleStream engineer-to-order (ETO) solution that captures and manages engineering knowledge and product rules to automate complex configuration, design, and documentation processes. It guides users on creating rule-based logic for generating 3D models, BOMs, quotes, and manufacturing data, integrating with CAD, PLM, and ERP systems to accelerate custom product delivery, improve accuracy, and streamline sales-to-order engineering workflows.